/*

 *

 * (C) 2020-26 - ntop.org

 *

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software Foundation,

 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

 *

 */

#ifndef _CARDINALITY_H_

#define _CARDINALITY_H_

#include "ntop_includes.h"

/* ******************************* */

class Cardinality {

 private:

  struct ndpi_hll hll;

 public:

  Cardinality() { memset(&hll, 0, sizeof(hll)); }

  ~Cardinality() { ndpi_hll_destroy(&hll); }

  void init(u_int8_t bits) {

    if (ndpi_hll_init(&hll, bits)) throw "init error";

  }

  bool addElement(const char* value, size_t value_len) {

    return (ndpi_hll_add(&hll, value, value_len) ? true : false);

  }

  bool addElement(u_int32_t value) {

    return (ndpi_hll_add_number(&hll, value) ? true : false);

  }

  u_int32_t getEstimate() { return ((u_int32_t)ndpi_hll_count(&hll)); }

  void reset() {

    memset(hll.registers, 0, hll.size); /* A lock might help here... */

  }

};

#endif /* _CARDINALITY_H_ */